1 files changed, 25 insertions, 12 deletions

diff --git a/include/linux/mmap_lock.h b/include/linux/mmap_lock.h
index 96e113e23d04..aab8f1b28d26 100644
--- a/include/linux/mmap_lock.h
+++ b/include/linux/mmap_lock.h
@@ -60,6 +60,29 @@ static inline void __mmap_lock_trace_released(struct mm_struct *mm, bool write)
 
 #endif /* CONFIG_TRACING */
 
+static inline void mmap_assert_locked(struct mm_struct *mm)
+{
+	lockdep_assert_held(&mm->mmap_lock);
+	VM_BUG_ON_MM(!rwsem_is_locked(&mm->mmap_lock), mm);
+}
+
+static inline void mmap_assert_write_locked(struct mm_struct *mm)
+{
+	lockdep_assert_held_write(&mm->mmap_lock);
+	VM_BUG_ON_MM(!rwsem_is_locked(&mm->mmap_lock), mm);
+}
+
+#ifdef CONFIG_PER_VMA_LOCK
+static inline void vma_end_write_all(struct mm_struct *mm)
+{
+	mmap_assert_write_locked(mm);
+	/* No races during update due to exclusive mmap_lock being held */
+	WRITE_ONCE(mm->mm_lock_seq, mm->mm_lock_seq + 1);
+}
+#else
+static inline void vma_end_write_all(struct mm_struct *mm) {}
+#endif
+
 static inline void mmap_init_lock(struct mm_struct *mm)
 {
 	init_rwsem(&mm->mmap_lock);
@@ -102,12 +125,14 @@ static inline bool mmap_write_trylock(struct mm_struct *mm)
 static inline void mmap_write_unlock(struct mm_struct *mm)
 {
 	__mmap_lock_trace_released(mm, true);
+	vma_end_write_all(mm);
 	up_write(&mm->mmap_lock);
 }
 
 static inline void mmap_write_downgrade(struct mm_struct *mm)
 {
 	__mmap_lock_trace_acquire_returned(mm, false, true);
+	vma_end_write_all(mm);
 	downgrade_write(&mm->mmap_lock);
 }
 
@@ -150,18 +175,6 @@ static inline void mmap_read_unlock_non_owner(struct mm_struct *mm)
 	up_read_non_owner(&mm->mmap_lock);
 }
 
-static inline void mmap_assert_locked(struct mm_struct *mm)
-{
-	lockdep_assert_held(&mm->mmap_lock);
-	VM_BUG_ON_MM(!rwsem_is_locked(&mm->mmap_lock), mm);
-}
-
-static inline void mmap_assert_write_locked(struct mm_struct *mm)
-{
-	lockdep_assert_held_write(&mm->mmap_lock);
-	VM_BUG_ON_MM(!rwsem_is_locked(&mm->mmap_lock), mm);
-}
-
 static inline int mmap_lock_is_contended(struct mm_struct *mm)
 {
 	return rwsem_is_contended(&mm->mmap_lock);